This application claims priority to international application PCT/JP98/02393 having a filing date of May 29, 1998.
1. Technical Field
The present invention relates to a vehicle monitor and a vehicle monitor method for displaying vehicle data.
2. Background Art
FIG. 1 is a block diagram of a prior art vehicle monitor. Referring to the drawing, reference numerals 1 and 2 denote ECUs which control the engine, ABS apparatus, and the like, measure data indicating vehicle-operating conditions (such as fuel consumption, engine speed etc.), and transmit data upon receipt of data transfer requests from an operation monitor 3. Reference numeral 3 denotes the operation monitor which transmits data transfer requests to the ECUs 1 and 2, and displays received data, and reference numeral 4 denotes a communication line connecting the operation monitor 3 with the ECUs 1 and 2.
The operation of the present invention will be described below.
Firstly, in order to realize operating conditions corresponding to accelerating and braking operations, the ECUs 1 and 2 control the engine, the ABS apparatus, and the like and at the same time measure fuel consumption, engine speed and so on.
On the other hand, in order to enable the driver of the vehicle to confirm the vehicle-operating conditions, the operation monitor 3 transmits data transfer requests for data indicating vehicle-operating conditions to the ECUs 1 and 2 through the communication line 4.
When data are sent thereto from the ECUs 1 and 2 in compliance with the data transfer request through the communication line 4, the operation monitor 3 takes up the data from the communication line 4 and displays such data, for example, on an indicator in the vehicle.
Thus although the driver of the vehicle can infer the vehicle-operating conditions, as is apparent from FIG. 1, it is necessary to provide a designated communication line 4 to connect the operation monitor 3 with the ECUs 1 and 2 for data transmission in the vehicle.
Further, the ECUs 1 and 2 are connected, not only with the operation monitor 3, but also with a self-diagnostic tester 5. (As shown in FIG. 2, the self-diagnostic tester 5 is a self-diagnostic tester connected by a connector 7 when the vehicle is inspected. The self-diagnostic tester 5 detects an abnormality or the like in the vehicle upon receipt of data from the ECUs 1 and 2). The ECUs are connected with the self-diagnostic tester 5 through a K line 6 and a connector 7 wherein the K line 6 is a communication line which is not normally used while the self-diagnostic tester 5 is unconnected.
Furthermore the K line 6 is a communication line in conformity with ISO 9141.
Since the prior art vehicle monitor is constructed as described above, the operation monitor 3 receives and displays data from the ECUs 1 and 2. However the problem has arisen that, in order for the operation monitor 3 to be able to obtain data from the ECUs 1 and 2, it is necessary not only to provide an operation monitor 3 in the vehicle, but also to provide a designated communication line 4 in the vehicle to connect the operation monitor 3 with the ECUs 1 and 2.
The present invention is proposed to solve the above mentioned problem and it is an object of the invention to obtain a vehicle monitor and a vehicle monitor method capable of displaying data indicating vehicle-operating conditions without providing a designated communication line in the vehicle.
The vehicle monitor of the present invention comprises a determination means which determines whether or not a self-diagnostic tester is connected to a communication line and which, when the result of the determination made by the determination means indicates that there is no connection, obtains data indicating vehicle-operating conditions from a collection means through a communication line and displays the data.
Thereby, it is possible to obtain data indicating vehicle-operating conditions by the use of an existing communication line to which the self-diagnostic tester is to be connected and, as a result, the effect is obtained that data indicating vehicle-operating conditions can be displayed without the need for a designated communication line in the vehicle.
The vehicle monitor of the present invention is adapted to use a K line as a communication line.
Thereby, the effect is obtained that data indicating vehicle-operating conditions can be obtained by using the K line when the self-diagnostic tester is unconnected, without the need for a designated communication line.
The vehicle monitor of the present invention is adapted to compare the potential on the communication line with a reference potential and thereby to determine whether or not there is a connection.
Thereby, the effect is obtained that the determination as to whether the connection is made or not is achieved without providing a complicated determination circuit.
The vehicle monitor of the present invention is adapted to disconnect a display means from the communication line when the self-diagnostic tester is connected with the communication line, and, when the self-diagnostic tester is not connected, to connect the display means to the communication line.
Thereby, the effect is obtained that processing of the self-diagnostic tester can be prevented from being disturbed when the self-diagnostic tester is connected, while data indicating vehicle-operating conditions can be obtained when the self-diagnostic tester is unconnected.
The monitor apparatus of the present invention is adapted to diagnose the vehicle-operating conditions on the basis of data indicating such conditions and to display the results of the diagnosis.
Thereby, the effect is obtained that the driver of the vehicle can confirm vehicle-operating conditions without the necessity of inferring operating conditions from data indicating such conditions.
In the vehicle monitor method of the present invention, a determination is made as to whether or not a self-diagnostic tester is in connection with a communication line. Data indicating vehicle-operating conditions are obtained from the communication line and is presented when the result of the determination indicates that the self-diagnostic tester is not connected with said communication line.
Thereby, the effect can be obtained that when the self-diagnostic tester is unconnected, data indicating vehicle-operating conditions can be obtained by using a K line without the need for a designated communication line.
The vehicle monitor method of the present invention is adapted to use the K line as a communication line.
Thereby, the effect is obtained that when the self-diagnostic tester is unconnected, data indicating vehicle-operating conditions can be obtained by using the K line without the need for a designated communication line.
The vehicle monitor method of the present invention is adapted to compare the potential on the communication line with a reference potential and to determine whether a connection is made or not on the basis of the result of the comparison.
Thereby, the effect is obtained that a determination as to whether or not the connection is made can be achieved without the need for providing a complicated determination circuit.
The vehicle monitor method of the present invention is adapted to disconnect the operation monitor presenting the data from the communication line when the self-diagnostic tester is connected with the communication line, and, when the self-diagnostic tester is not connected, to put the operation monitor into connection with the communication line.
Thereby, the effect is obtained, while data indicating vehicle-operating conditions can be obtained when the self-diagnostic tester is not in connection, processing of the self-diagnostic tester can be prevented from being disturbed when the self-diagnostic tester is in connection.
The vehicle monitor method of the present invention is adapted to diagnose vehicle-operating conditions on the basis of data indicating vehicle-operating conditions to display the results of the diagnosis.
Thereby, the effect is obtained that the driver of the vehicle can confirm vehicle-operating conditions without the necessity to infer such operating conditions from data indicating vehicle-operating conditions.